Insulator



W. T. JERVEY Sept. 7, 1937.

INSULATOR Filed Dec. 11, 1935 2 Sheets-Sheet l INVENTOR BY 14 7TJERVEY j %(m:% mail p 1937- w. T. JERVEY 2,092,515

INSULATOR Filed Dec. 11, 1935 2 Sheets-Sheet 2 lNl EN TOR v W. TJER VEY A 7'7'ORNEY Patented Sept. 7, 1937 UNITED STATES PATENT OFFICE Bell Telephone Laboratories, Incorporated,

New York, N. Y., a corporation of New York Application December 11, 1935, Serial Ne. 53,939

7 Claims.

This invention relates to insulators and more particularly to insulators for line wires of electrical systems.

The object of this invention is to maintain the spacing of line wires at a predetermined minimum distance from line wires adjacent thereto.

A feature of this invention resides in the particular form and structure of an insulating member.

Another feature resides in holding means for holding the insulator in a required position.

In the drawings:

Fig. 1 shows a system of open-wire lines supported on poles and having the invention applied to the line wires;

Fig. 2 is a plan view of the insulator applied to a line wire, the line wire being shown in crosssection; the insulator and wire in Fig. 2 are shown enlarged relative to Fig. 1;

Fig. 3 is an edge view of the insulator applied to a line wire and viewed from the left of Fig. 2;

Fig. 4 is a plan view corresponding to Fig. 2 but including a modification of the holding means;

Fig. 5 is an edge view of the device shown in Fig. 4 and viewed from the left of Fig. 4;

Fig. 6 is a view corresponding to Fig. 5, showing a portion of Fig. 5 and with the holding means in a position released relative to the line wire;

Fig. '7 is a view corresponding to Figs. 2 and 4 but including a further modification of the invention;

Fig. 8 is an edge View of the structure shown in Fig. 7 and viewed from the left of Fig. 7;

Fig. 9 is a view corresponding to Fig. 8 but showing only a. portion of Fig. 8 and with the holding means in a position released relative to the line wire;

Fig. .10 is a plan view of a towing device for adjusting the insulator to a required position on a. line wire, the towing device being shown as engaging an insulator on a line wire preparatory to being used for towing the insulator to the position required;

Fig. 11 is an edge view of the apparatus shown in Fig. and viewed from the right of Fig. 10; and

Fig. 12 is a plan view corresponding to Fig. 10 but showing the towing device releasing the holding means of the insulator.

In systems of open-wire lines of electrical communication systems it is necessary, where bare conductors are used as the line wires, to maintain the wires separated from each other. To

prevent false signals it is also necessary to keep the wires spaced from each other by at least some predetermined distance.

The insulator shown in Fig. 2 is a round disc I of insulating material having a transversely eX- 5 tending aperture 2 in its diametrical center adapted to receive a line wire 3. The center of the aperture 2 is preferably slightly ofifset rela tive to the diametrical center of the disc I. A slot 4 extending from the periphery of the disc I 10 to the aperture 2 is provided to permit placement of the insulator on a line wire 3 without having to thread an end of the line wire through the aperture 2 in the disc I. The slot 4 extends from the periphery of the disc 6 in a line oifset from 15 the aperture 2 to a point in a horizontal line with the aperture 2 from whence the slot 4 turns at about an angle of 90 degrees into the aperture 2. A plurality of comparatively large apertures 5 are provided in the disc I. The apertures 5 may be arranged radially relative to the aperture 2 as shown in Fig. 2 or may be located at other points in the disc. The apertures 5 are provided .3 in the disc I to reduce the wind resistance of the device and to provide openings through which gunshot pellets or other like missiles aimed at the device may pass without striking the insulator. The aperture 2 is preferably made somewhat larger in diameter than the line wire 3 and slightly larger in diameter than the width of the slot 4, the slot 4 being only of sufficient width to readily receive the line wire 3.

Attached to opposite faces of the disc I are holding arms 6-43. The arms 6-B may be formed from sheet metal or other resilient material. The material employed, however, should be somewhat harder than the material of a line Wire. One end of each arm 6 is secured to the disc I at a point about midway between the aperture 2 and the periphery of the disc I. The means for securing the arms 65 to the disc I may be rivets l--I or like fastening means which pass through apertures in the arms 6-45 and transversely through the disc I. The arms 66 spread outwardly, one from each flat surface of the disc, and. extend slightly upward from the point of attachment. The arms are wisted at about an intermediate point 8 to present flat surfaces toward the line wire 3 as shown in Fig. 3. The free ends of the arms 66 continue upwardly from the point of twist 8 and continue to diverge from the fiat surface of the disc I to a point slightly above the center of the aperture 2 where they are bent to form hooks 99 to hook over the line wire 3. The hooks 9-9 are preferably in the form of a shepherds crook.

In applying the device shown in Figs. 2 and 3 to a line wire is shown in Fig. 1 the insulator is hooked over a line wire 3 by placing the insulator over the line wire so that the slot I is in line with the wire. The insulator is then lowered about the line wire 3 till the line wire 3 is even with the free ends of the hooks 9-3. The hooks 9-9 are then manually slipped over the line wire 3 and the insulator is positioned so as to bring the line wire further within the hooks 9-9. By further pressing the insulator downwardly on the line wire 3 the portion of the wire passing through the disc I is brought into the horizontal portion of the slot Q and is then pulled by the hooks 9-9 into the aperture 2. When the insulator is applied to the line wire 3 the plane of the disc i is perpendicular to the line wire 3.

When the arms 6-3 are in normal position as shown in Fig. 3 and the insulator has been applied to a line wire 3 the hooks 9-9 pass diagonally across the line wire 3 and the outer edges IB-IE of the hooks 9-9, where the hooks cross the line wire, bear against the upper surface of the line wire 3 with sufficient pressure to prevent the insulator from being moved longitudinally along the line wire. If the edges Iii-Iii of the hooks 9-9 are comparatively sharp and are harder than the material of the line wire 3 the upper surface of the line wire 3 will be slightly indented by the edges iii-Ill of the hooks. The hooks 9-9 will then have sufficient grip on the line wire 3 to prevent movement of the insulator along the line wire. The arms IS-6, therefore, serve as holding means for the insulator and maintain the insulator in an adjusted position on the line wire 3. To move the insulator longitudinally along the line wire it is only necessary to press the arms 6-6 simultaneously toward the disc I and thereby draw the edges Iii- IU of the hooks 9-9 from engagement with the line wire 3 and then slide the insulator to a required position. When the arms 6-6 are released they spring apart again and the edges Ill-Iii of the hooks 9-9 press against the line wire 3 with sufficient force to prevent movement of the insulator along the line wire.

With the insulators placed on the line wires 3 as shown in Fig. l the line wires 3 are prevented by means of the insulators from coming into contact with each other even though a comparatively high cross wind or other force may be tending to move the line wires. The insulator may be made of any required diameter to maintain the line wires separated from each other a predetermined minimum distance.

If line wires are equipped with insulators, of the type described, the poles supporting the line Wires may be spaced a greater distance apart, or the line wires may be more closely spaced, than is normally the custom where such insulators are not provided.

In Figs. 4, 5, and 6 a modification of the invention is shown. In this case the holding means for the insulating disc I are resilient arms I I-Il attached to opposite faces of the disc I in the same manner as the arms 6-6 in Figs. 2 and 3. The arms II-II are substantially flat and terminate at their free ends in hooks I2-I2. The hooks IZ-IZ diagonally cross the line wire 3 as shown in Fig. 5 and edgewise relative thereto. When the arms I I-I I are in normal position the edges I3-I3 of the hooks I2-I2 bear against the upper surface of the line wire 3 with suffithe insulator in the position to which it has been I brought. In Fig. 6 the arms II-II are shown as pressed toward the disc I to release the edges I3-I3 from engagement with the wire 3.

In Figs. '7, 8, and 9 another modification of the invention is shown. The disc I in these figures like the disc I in Figs. 4, 5, and 6 is identical with the disc I shown and described with reference to Figs. 2 and 3. In this case, however, the holding means for the insulator are curved spring arms I l-I4 made of flat sheet resilient material. The spring arms I l-I4 are attached at one end to opposite faces of the disc I by rivets 7-1 or other fastening means as in embodiments. The spring arms I i-I4 are notched at their free ends to form hooks'I5-I5 to engage the line wire 3. The hooks I5-I5 face the line wire 3. This arrangement permits bringing the line wire 3 upwardly through the slot 4 directly into the horizontal portion of the slot 4 and directly into the hooks I5-I5; No manual pressing of the line Wire 3 into the hooks is required with this device such as is required in connection with the structures shown in Figs.

the other 2, 3, 4, 5, and 6. In the structure shown in Figs. '7, 8, and 9 the outer edges IB-IG of the hooks Iii-I5, when in normal position as shown in Fig. 8, press against the upper surface of the line wire 3 and engage the line wire 3 with sufficient pressure to maintain the insulator in a required position. To move the insulator along a line wire 3, longitudinally of the line wire, it is only necessary to press the spring arms Ifi-M toward the disc I as shown in Fig. 9 sufficiently to move the edges lE-IB of the hooks I5-I5 from engagement with the line wire and then slide the insulator to a, required position. When the spring arms I l-I l are released they will spring apart to their normal position as shown in Fig. 8 and the edges I'd-I6 of the hooks |5I5 will engage the line wire 3 and hold the insulator in the adjusted position.

Figs. 10, 11, and 12 show a towing device I'I for moving quired position on a line wire 3. The towing device I1 is shown as being used in applying an insulator, constructed as shown in Figs. 2 and 3, to a line wire 3.

The towing device I! comprises two spaced upright bars I8 and I9 held in spaced relation at about their central portions by means of a crossbar 28. One end of the cross-bar 20 is rigidly secured to the upright bar I8 by the rivetsZI or other like fastening means. The upright bar I9 is centrally pivoted on the other end of the crossbar 20 by means of a pin or rivet 22. The upper ends of the upright bars I3 and I9 serve asjaws to engage the insulator. upright bar I8 terminates in a flange forming .a stationary jaw 23. The upper end of the upright bar I9 terminates in a flange forming a movable jaw 2s. The jaws 23 insulators of the type described to a re- The upper end of the '1 and 24 are equipped with 7 adapted to receive the upper portions of the arms 6 of the insulator.

Pivotally attached to the lower end of the arm l-Q by a pin 27 is a holding bar 28. The free end of the holding bar 28 is cut away on the lower corner to provide a shoulder 29 and a reduced end portion to engage a stud 3| secured. to the rear surface of the bar it. Attached to the front face of the holding bar 28 near its free end and adapted to inner edge of the lower end of bar i8 is a circular disc Projecting normal to the outer flat surface of the circular disc 32. and secured thereto in an eccentric position is a rod 33. Ihe rod 33 is comparatively long and extends outwardly beyond the front surface of the bar l8. The free end of the holding bar 26 is normally held in a raised position by means of a spring 34 as shown in Fig. 12. The spring 3 3 is attached at its lower end to the holding bar 28 by having a hook on its lower end extending through an aperture in the disc and through an aligned and corresponding aperture in the holding bar 28. The upper end of the spring is hooked through an aperture in the cross-bar 26. A latch 35 is secured to the lower end of the bar IE to hold the holding bar 28 in a lowered position as shown in Fig. 10. The latch has a spring pressed bolt 35 extending, when in projected position, beyond the inner edge of the lower portion of the bar 58 and in line with the top of the when the holding bar is swung downward to its lowermost position. The spring ill in the latch 85 normally maintains the bolt 35 in projected position. The bolt 35, however, may be manually wi hdrawn against the spring 3? as shown in Fig. 12 by means of a chain When an insulator been applied to lino wire ii, in the manner previously described, the towing device ll may be attached to the insulator by placing the split pins and 26 in en gagcrnent with the upper ends of the arms li-S as shown in Fig. 12. By manually pulling down the holding bar 23 from the position shown in Fig. 12 to the position shown in Fi and the consequent pressing of the circular disc 32 against the inner edge of the lower portion of the bar Ii! the lower ends of the bars l8 and I9 are spread apart from the position shown in Fig. 12 to the position shown in Fig. it). By the consequent movement of the upper end 0 the bar H) the arms 6-5 of the insulator are pressed toward the disc l to a sufficient extent to remove the outer edges lt-lil of the hooks 9-9 from engagement with the line wire The holding bar 28 when nearing its lowermost position brings the rod 33 into engagement with the sloping upper surface of the bolt 35 of the latch 35. As the holding bar 23 is moved further downward the latch bolt 35 is forced inwardly against its spring 31. Further downward movement of the holding bar it brings the rod past the latch bolt and brings the shoulder 2t and the reduced end 3b of the holding bar into engagement with the stud 3!. The latch bolt 36 is then moved by its spring 31 to extend over the upper surface of the rod 33 to retain the holding bar 28 in its lowermost position. The holding bar 23 prevents opening of the jaws 23 and 25. With the towing device ll clamped to the insulator and holding the outer edges 28-40 of the hooks 9-9 of the insulator from engaging the line wire 3, as shown in Figs. 10 and ll, the insulator may be pulled along the line wire. Tow lines 39 and 48 are respectively attached to the upper ends of the bars l8 and is to enable linemen to tow the device to a required position between supporting poles of a line system. When the insulator has been towed to a required position the latch bolt 3'5 may be manually withdrawn from engagement with the rod 33 by means of the pull chain This action releases the holding bar 3 and permits the spring M to swing the holding her upwardly on its pivot point as shown in Fig. 12. The spring pressure of the arms d-il of the insulator when in the position shown in Fig. l0 will propel the arms 5-6 outwardly from the flat surfaces of the disc l and bring the outer ed es il-l3 or" the hooks into engagement with the line wire or movement of the insulator e 3. The spring pressure in 6--ii will also force the upper ends of arms and Hi further apart and permit some free swinging the towing device ll. By alternate pulling on the tow lines 23 and 39 the towing ll ay be dislodged from engagement with the insulator.

What is claimed is:

1. An insulator a line wire comprising a centrally apertured disc of insulating material, the aperture being slightly larger than the diameter of the line wire, a slot of sufiicient width n the disc to receive the line wire, said slot ex tending from the central aperture in the disc to the periphery of the disc, and serving as an opening to permit the e wire to be rought to extend transversely central portion of disc, c1 disc bctwec. ter

tli 'ough the disc and adapted to en line wire passing through the central oper ture in said disc, hooks on the free ends of said is and hooks to engage the toward said disc P from engagement with the lir wire comprising a said disc having I loter of the disc to the central aperture, sa 1 slot and the central aperture g as an opening to permit placement of said disc about the line wire so that the line wire will extend transversely through the central portion oi said disc, spring arms at tached to the fiat faces of said disc, each of said a. having a free end extending away from til plane of the disc and to a point'in line with central l of each i s id disc and a sharp rtion on each 1001?. adapte l to engage the line wire when he 1. central aperture in bendable from engage"- extends through the disc, s-id arms being l said disc to remove the hooks t with the line wire.

3. In an insulator for a line wire, an apertured disc of insu g material angularly slotted from its pet: and apertured at its center to 1 it a line wire to brought to the central portion or" said disc, a pair of spring arms, said arms being attached to said disc at a point offset from the diainetrical center of said disc and said arms extending outwardly of said disc and upwardly from the point of attachto a line projected from the axis of said disc and hooked free on said arms adapted to hook over a line wire, said arms normally pressing their hooked free ends against the line wire to retain the insulator against sliding movements along the line wire, but being flexible toward said disc to release their gripping action on the line wire to permit movement of the insulator along the line wire.

4. An insulator for a line wire comprising an apertured flat disc of insulating material angularly slotted from its perimeter and centrally apertured at the inner end of the slot to permit bringing of a line wire to the central portion of said disc, a pair of spring arms attached to said disc at a point intermediate the perimeter and the axis of said disc, free ends of said arms extending outwardly of the plane of said disc and upwardly from the point of attachment, each of said arms having a hooked free end diagonally crossing a line projected from the axis of said disc and normal to the plane of said disc, the hooked free ends of said arms having sharp side edge portions and said arms being each adapted to present a sharp side edge of the hooked free end against a line wire when the line wire extends through the central aperture in the disc, said arms normally serving to prevent sliding of the insulator along the line wire, but being flexible toward'the faces of said disc to release the hooked free ends from engagement with the line wire to permit sliding of the insulator along the line wire to a required position.

5. An insulator for a line wire comprising an apertured fiat disc of insulating material angularly slotted from its perimeter and centrally apertured at the inner end of the slot to permit the line wire to be brought transversely through the central portion of said disc, a pair of spring arms attached to said disc at a point intermediate the perimeter and the axis of said disc, free ends of said arms extending outwardly of the plane of said disc and upwardly from the point of attachment, each of said arms having a degree twist at a point intermediate the ends of the arm and a hooked free end diagonally crossing a line projected from the axis of said disc and normal to the plane of said disc, the

hooked free ends of said arms being each adapted to present an edge of the hooked free end against a line wire when the line wire extends through the central aperture in the disc and said arms being bendable toward said disc to release the hooked free ends from engagement with the line wire.

6. An insulator for a line wire comprising an apertured disc of insulating material angularly slotted from its perimeter and centrally apertured at the inner end of the slot to permit the line wire to be brought transversely through the central portion of said disc, a pair of flat spring arms attached to said disc at a point intermediate the perimeter and the axis of said disc, said arms being progressively curved upwardly and outwardly of the point of attachment and toward a line projected normal to the plane of said disc and from the axis and hooks on the free ends of said arms, said hooks following the curvature of said arms and normally presenting edge portions of the hooks against the line wire when the line wire extends through the insulator and said arms being bendable toward said disc to release the hooks from engagement with the line wire.

7. An insulator for line wires comprising a disc of insulating material centrally apertured to receive a line wire, an inverted L-shaped slot extending from the perimeter of the disc to the central aperture, the central aperture and said slot serving as an opening through which the line wire may be brought to extend transversely through the central portion of said disc; 2. pair of oppositely bowed spring arms attached to said disc at a point intermediate the perimeter and the axis of said disc, said arms curving upwardly and outwardly of the point of attachment to the axis line of said disc, and hooked free ends on said arms having their hooks facing against the direction taken by the upper end of said Inverted L-shaped slot and disposed in planes oiiset from the plane of said disc.

WILLIAM T. JERVEY. 

